404345221 has 32 divisors (see below), whose sum is σ = 513520128. Its totient is φ = 310210560.

The previous prime is 404345203. The next prime is 404345257. The reversal of 404345221 is 122543404.

404345221 = T₁₁₈ + T₁₁₉ + ... + T₁₃₄₃.

It is a happy number.

It is not a de Polignac number, because 404345221 - 2²⁵ = 370790789 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (404340221) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 659311 + ... + 659923.

It is an arithmetic number, because the mean of its divisors is an integer number (16047504).

Almost surely, 2^404345221 is an apocalyptic number.

It is an amenable number.

404345221 is a deficient number, since it is larger than the sum of its proper divisors (109174907).

404345221 is a wasteful number, since it uses less digits than its factorization.

404345221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 901.

The product of its (nonzero) digits is 3840, while the sum is 25.

The square root of 404345221 is about 20108.3371018093. The cubic root of 404345221 is about 739.4646852849.

Adding to 404345221 its reverse (122543404), we get a palindrome (526888625).

The spelling of 404345221 in words is "four hundred four million, three hundred forty-five thousand, two hundred twenty-one".